Energy-Controllable Manipulation on Surface Waves and Propagating Waves by Bifunctional Metasurfaces

Area of Science:

• Photonics and Metamaterials
• Electromagnetics and Wave Phenomena
• Integrated Optics

Background:

• Controlling propagating waves (PWs) and surface waves (SWs) typically requires separate devices, hindering integrated optics.
• Existing metasurfaces for simultaneous PW and SW control often rely on complex dynamic helicity variations of circularly polarized (CP) light.

Purpose of the Study:

• To propose and demonstrate a metasurface design capable of simultaneously controlling PWs and SWs.
• To overcome the limitations of separate devices and complex control mechanisms in current integrated optics.
• To enable tailored manipulation of both far-field and near-field electromagnetic waves on a single platform.

Main Methods:

• Designing metasurfaces encoded with both resonance and geometric phases.
• Utilizing co- and cross-polarized output channels under CP light excitation.
• Experimentally realizing microwave metadevices for converting left circular polarization (LCP) beams.
• Numerically demonstrating energy distribution control in output channels.

Main Results:

• Successful experimental realization of two microwave metadevices.
• Demonstrated simultaneous control of PWs and SWs with predetermined wavefronts from LCP incident beams.
• Numerical validation of designing metadevices with specific energy distributions for PWs and SWs.

Conclusions:

• The proposed metasurface design offers a simplified and integrated approach to control both PWs and SWs.
• This work paves the way for ultra-compact platforms for manipulating electromagnetic waves in both far- and near-fields.
• The findings have significant implications for future applications in integrated optics and advanced photonic devices.